Mac OS X's application Help menu is extremely handy, searching for (and pointing out) any action within an application's title bar menu as-you-type. Even better? It's keyboard-shortcut handy, and as such can be a real timesaver for shortcut junkies.

In general the fastest route to most actions in an application is via a dedicated keyboard shortcut (it's always going to be quicker to hit Cmd+L than digging through menus or moving to your mouse), but when you're in an application you're unfamiliar with, you want to perform an action that you don't use all that often, or the menu item just doesn't have a shortcut associated with it, Mark Dalrymple from Borkware Miniblog points out that the built-in Help menu search is extraordinarily useful for jumping straight to what you need:

As Apple blog Daring Fireball points out, you can streamline this process that much more by using OS X's Help menu shortcut, which by default is Cmd+Shift+/ (which translates to Cmd+?). Unfortunately the shortcut doesn't work in every application (Firefox unfortunately hijacks the shortcut to go to this Firefox help web page), but it's still a very useful shortcut to keep in mind.

Finally, if you're using the Help shortcut to access an action that you wish you could access via one dedicated keyboard shortcut, you can do that, too.